The purpose of this study is to determine if infrequent administration of oral vitamin D megadoses is effective treatment to maintain serum 25-hydroxyvitamin D(3) above target levels of 50-75 nmol/L. The investigators hypothesize that 100 000 IU or at least 200 000 IU vitamin D3 in every three months would be effective and safe treatment to achieve the target levels.

10 ml (placebo group) or 5 ml (100 000 IU vitamin D3 group) oil per os every three months for one year

Dietary Supplement: calcium carbonate

1000 mg calcium per os every day for one year

Placebo Comparator: placebo every three months

Other: olive oil

10 ml (placebo group) or 5 ml (100 000 IU vitamin D3 group) oil per os every three months for one year

Dietary Supplement: calcium carbonate

1000 mg calcium per os every day for one year

Eligibility

Ages Eligible for Study:

70 Years and older

Genders Eligible for Study:

Female

Accepts Healthy Volunteers:

Yes

Criteria

Inclusion Criteria:

female

70-80 yrs old

Exclusion Criteria:

disease or medication affecting calcium homeostasis

renal failure (Pt-GFRe-CG < 35 ml/min)

Contacts and Locations

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study.
To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below.
For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01067898

Locations

Finland

Division of Endocrinology, Department of Medicine, Helsinki University Central Hospital